Intersomatic cage, intervertebral prosthesis, anchoring device and implantation instruments

Abstract

An intersomatic cage, an intervertebral prosthesis, an anchoring device and an instrument for implantation of the cage or the prosthesis and the anchoring device are provided. An intersomatic cage or an intervertebral prosthesis fit closely to the anchoring device, which includes a body of elongated shape on a longitudinal axis, of curved shape describing, along the longitudinal axis, an arc whose dimensions and radius of curvature are designed in such a manner that the anchoring device may be implanted in the vertebral plate of a vertebra by presenting its longitudinal axis substantially along the plane of the intervertebral space, where the anchoring device is inserted, by means of the instrument, through a slot located in at least one peripheral wall of the cage or on at least one plate of the intervertebral disc prosthesis to penetrate into at least one vertebral plate.

The invention claimed is: 
     
       1. An intervertebral disc prosthesis configured for implantation in an intervertebral space between adjacent vertebrae of a spinal column, the intervertebral disc prosthesis comprising:
 a curved anchor comprising a flat body extending from a penetration end to an abutment end and including a curved shape extending the length of the body along a longitudinal axis that describes an arc, wherein a first axis extending through the penetration end and a second axis extending through the abutment end create an angle based on a radius of the curved shape, and wherein the curved anchor includes a projecting lug disposed along the abutment end of the curved anchor, the projecting lug extending laterally from opposing sides of the flat body or extending toward an interior concave side of the flat body; and 
 first and second plates, at least one of the first and second plates including a receptacle traversing at least a portion thereof, the receptacle configured for passage of the anchor and for orientation of the anchor during implantation of the anchor in a vertebra. 
 
     
     
       2. The intervertebral disc prosthesis according to  claim 1  in which the receptacle comprises a slot having a first stop configured to mate with a second stop of the anchor. 
     
     
       3. The intervertebral disc prosthesis according to  claim 2  in which the first stop comprises a recess configured to accommodate a projecting lug of the anchor. 
     
     
       4. The intervertebral disc prosthesis according to  claim 2  in which the first stop comprises a peripheral surface of the first or second plate configured to accommodate a projecting lug of the anchor. 
     
     
       5. The intervertebral disc prosthesis according to  claim 1 , in which the receptacle comprises a stop configured to mate with a flexible lug of the anchor to oppose withdrawal of the anchor from the receptacle. 
     
     
       6. The intervertebral disc prosthesis according to one of  claim 1  in which at least one of the first and second plates comprises an attachment device configured to mate with a gripper of an implantation instrument. 
     
     
       7. The intervertebral disc prosthesis according to  claim 1  in which the intervertebral disc prosthesis comprises top and bottom surfaces, at least one of which having notches configured to prevent movement of the intervertebral disc prosthesis when the intervertebral disc prosthesis is implanted. 
     
     
       8. The intervertebral disc prosthesis according to  claim 1  in which at least one of the first and second plates has top and bottom surfaces through which mean planes pass, with the mean planes forming an angle configured to impose a lordosis on the adjacent vertebrae. 
     
     
       9. The intervertebral disc prosthesis according to  claim 1  in which each of the first and second plates comprises a receptacle traversing at least a portion thereof, each receptacle configured for passage of an anchor having a body with a curved shape along a longitudinal axis that describes an arc and for orientation of the anchor during implantation of the anchor in a vertebra. 
     
     
       10. An intervertebral disc prosthesis comprising:
 a cage including a disc shaped body comprising a superior vertebral contacting surface and an inferior vertebral contacting surface, the disc shaped body further comprising a posterior portion including an anchor passage angling from a first opening on a posterior face to a second opening on the superior vertebral contacting surface; and 
 a curved anchor comprising a flat body extending from a penetration end to an abutment end and including a curved shape extending the length of the body along a longitudinal axis that describes an arc, wherein a first axis extending through the penetration end and a second axis extending through the abutment end create an angle based on a radius of the curved shape, wherein the curved anchor is insertable within the anchor passage to anchor the prosthesis to a vertebral body, and wherein the curved anchor includes a projecting lug disposed along the abutment end of the curved anchor; the projecting lug extending laterally from opposing sides of the flat body or extending toward an interior concave side of the flat body. 
 
     
     
       11. The intervertebral disc prosthesis of  claim 10 , wherein the radius of curvature of the curved anchor is constant between the penetration end and the abutment end. 
     
     
       12. The intervertebral disc prosthesis of  claim 10 , wherein the radius of curvature varies between the first and second ends. 
     
     
       13. The intervertebral disc prosthesis of  claim 10 , wherein the anchor passage comprises a slot having a first stop configured to mate with a second stop of the curved anchor. 
     
     
       14. The intervertebral disc prosthesis of  claim 13 , wherein the first stop comprises a recess configured to accommodate a projecting lug of the curved anchor. 
     
     
       15. The intervertebral disc prosthesis of  claim 13 , wherein the first stop comprises a peripheral surface of the posterior face configured to accommodate a projecting lug of the curved anchor. 
     
     
       16. The intervertebral disc prosthesis of  claim 10 , in which the anchor passage comprises a stop configured to mate with a flexible lug of the curved anchor to oppose withdrawal of the anchor from the anchor passage. 
     
     
       17. The intervertebral disc prosthesis of  claim 10 , wherein the posterior face comprises an attachment mechanism configured to mate with a gripper of an implantation instrument. 
     
     
       18. The intervertebral disc prosthesis of  claim 10 , wherein at least a portion of both the superior vertebral contacting surface and the inferior vertebral contacting surface include notches configured to prevent movement of the intervertebral disc prosthesis when the intervertebral disc prosthesis is implanted.